A portable scanned beam display may be utilized to display information via a larger image while still maintaining a smaller form factor. Thus, such a scanned beam display may provide the output function for a mobile device, however an input function may still be required. Typically for a mobile telephone or other similar smaller form factor device, the input function is accomplished by a smaller sized keyboard. Computer users are used to having a larger sized keyboard available and in addition a pointing device, typically a mouse. Known approaches for implementing a touch screen for input typically require some form of planar arranged hardware to detect the absolute X-Y position of the pointing device, which is typically a stylus. Such hardware implementations may comprise capacitive sensing arrays, resistive sensing arrays, wire grid arrays, optical coupling arrays, and pressure sensing arrays, all requiring a two-dimensional hardware structure. In order to provide suitable resolution of movement for the typical user, these hardware structures end up being too bulky for use with portable devices such as cellular telephones.
It will be appreciated that for simplicity and/or clarity of illustration, elements illustrated in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity. Further, if considered appropriate, reference numerals have been repeated among the figures to indicate corresponding and/or analogous elements.